Water jet nozzle for loom

ABSTRACT

A water jet nozzle for a loom includes a nozzle member having a rear end portion, an interior orifice formed in the rear end portion, a stabilizer integrally connected to the orifice for adjusting water flow in the rear end portion of the nozzle member and a needle arranged centrally of the orifice for feeding out a weft yarn. The orifice and stabilizer define an annular groove therebetween and are made of a material having a high hardness and high corrosion resistance. The orifice and stabilizer are preferably made of a material such as a cemented carbide, cermet, or ceramic having a modulus of elasticity of at least 1.5×10 4  kg/mm, an H R  A hardness of at least 85 and a flexural strength of at least 50 kg/mm 2 . The stabilizer is constructed of a plurality of elongated blades of equal width arranged in concentric parallel spaced relation to define therebetween a plurality of elongated slits of equal width arranged in concentric parallel spaced relation. The water jet nozzle is particularly useful for high-speed looms.

The present invention relates to a water jet nozzle for use with ahigh-speed loom.

BACKGROUND OF THE INVENTION

Structures of water jet nozzles for use with a loom are disclosed inJapanese Utility Model Unexamined Publication (KOKAI) Nos. 61-155386 and62-88779.

In recent years, as disclosed in these publications, a dominant type ofwater jet nozzle incorporates a stabilizer for straightening water flowof the water jet nozzle with speed-up in an automatic loom.

This type of prior art water jet nozzle, as shown in FIG. 5, is soconstructed that an orifice E and a needle F inserted concentricallywith the orifice E are provided at a top of a body D formed with a poolC communicating with a water injection hole B of a holder A. Thestructure of the water jet nozzle is such that the water injected viainjection hole B of the holder A jets out from a gap between the orificeE and the needle F. The water jet nozzle performs a function tointermittently feed, between warps stretched from a tip of the needle Fto an unillustrated loom, a weft yarn charged in from a cavity G of theneedle F.

When feeding out the weft yarn, it is required that a jet flow formed inthe path from the water injection hole B to the gap between the orificeE and the needle be rectified as much as possible.

For this straightening, a resinous stabilizer H having a constructionshown in FIG. 6 is so disposed as to be contiguous to a rear end of theorifice E composed of hardened steel.

The resinous stabilizer H is manufactured simply by injection moldingand also simply assembled by setting it in a space at a rear part of theorifice E made of hardened steel. The stabilizer H exhibits a remarkableeffect for a loom having a weftwise feeding number of approximately400-750 times/min under a water pressure of about 25 kg/cm².

With the further advancement of speeding up the loom in recent years,working conditions oriented thereto are that water pressure is 30-40kg/cm² ; water flow rate reaches 30 -40 m/sec.; and the number ofinsertions of weft yarn exceeds 1000 times/min.

In the water jet nozzle equipped with a resinous stabilizer, thematerial of which the stabilizer is formed is insufficient in itshardness and strength, resulting in an intensive wear caused by thewater flow and in a short life span thereof. Besides, it is impossibleto set the thickness of a blade unit to 0.2 mm or under. At a high flowrate of more than 30 m/sec., the water pressure drops due to fluidresistance, and the weftwise feeding number is limited to 750 times/min.Under such conditions, it is absolutely impossible to achievehigher-speed feeding of the weft yarn.

In addition, vibrations and swirls are caused due to deformation of thestabilizer itself when the water flows at a high velocity. Thissituation in turn makes the insertions of weft yarn irregular, and therearise problems of causing both a drop in availability factor concomitantwith a stagnation of the loom as well as a decline in the quality offabrics woven.

The conventional water jet nozzle generates water jets from the orificeand needle, and the unit for feeding out the weft yarn is made at bestof a hardened steel. Hence, wear resistance and corrosion resistance arenot sufficient, as a result of which the device decreases in its lifespan and associated components have to be replaced. Not only does theresinous stabilizer conceived as a replaceable component decrease inavailability factor, but also the loom itself is thereby reduced in thesame factor.

In order to improve the wear resistance, a structure of embedding acylindrical ceramic body in an inside diametrical part of the tip of theconventional needle made of hardened steel and bonding it thereto hasbeen proposed. This structure, however, presents the problem of theceramic body falling off during use.

SUMMARY OF THE INVENTION

Accordingly, it is a primary object of the present invention to providea novel water jet nozzle for performing high-speed and stable weaving.

Another object of the present invention is to provide a water jet nozzlecapable of reducing resistance caused by straightening of water jets.

Still another object of the present invention is to provide a water jetnozzle capable of improving hyperfine machinability of a needle tip andenhancing the function of the nozzle itself.

A water jet nozzle according to the present invention is constructed insuch a way that a high pressure water flow from a needle and an orificeis jetted; a unit for feeding out a weft yarn is composed of a materialhaving a high hardness and corrosion resistance; and the orifice is madeintegral with a stabilizer.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood by reference to theaccompanying drawings, in which:

FIG. 1 is a sectional view in perspective of a nozzle member accordingto an embodiment of the present invention;

FIG. 2 is a cross-sectional view of the stabilizer shown in FIG. 1;

FIG. 3 is a sectional view of the nozzle member shown in FIG. 1 inconjunction with a needle;

FIG. 4 is a sectional schematic illustration of a tapered portion of thenozzle member;

FIG. 5 is a sectional view of a water jet nozzle according to the priorart; and

FIG. 6 is a perspective view of a resinous stabilizer for a water jetnozzle of the prior art.

Throughout the drawings, the numerals designate components as follows:

    ______________________________________                                        1:     nozzle number   2:    body                                             3:     orifice         4:    annular groove                                   5:     stabilizer      6:    slit                                             7:     blade           8:    top end of blade                                 9:     needle          10:   top end of orifice                               11:    inlet of orifice                                                                              12:   tapered portion                                  W:     water injected                                                         ______________________________________                                    

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Suitable material of high hardness and corrosion resistance includes theuse of sintered cemented carbides, cermets and ceramics. An arbitrarymaterial can be employed on the condition that its modulus of elasticityis more than 1.5×10⁴ kg/mm² and its hardness is H_(R) A 85 or greater.

Since the stabilizer for straightening the injected water requires ahyperfine machinability, the flexural strength of suitable material istherefore 50 kg/mm², preferably 75 kg/mm² or larger.

To be specific, the sintered cemented carbides include materials groupedin accordance with JIS symbols, P, M, K, V and E which are used forcutting tools, wear resistant tools and mining tools. As cerments, theremay be exemplified materials mainly composed of titanium carbideexhibiting strengths, wear resistance, corrosion resistance and ahyperfine machinability. These materials are effective in obviating theforegoing problems in the prior art.

Where ceramic materials are utilized, in the great majority of cases,they exhibit more excellent corrosion resistance and wear resistancethan in the sintered cemented carbides and cermets. On the other hand, agood many ceramic materials are unsatisfactory in terms of theirflexural strengths and are therefore to be selected depending on whetheror not they exhibit a hyperfine machinability.

A wide variety of ceramic materials are prepared, i.e., AL₂ O₃, Si₃ N₄,ZrO₂ and SiC. Other materials chiefly composed of nitride, boride andcarbide or composites obtained by mixing two or more kinds of thesematerials are also exemplified. In the case of machining the material tohave a wall thickness of more than 0.1 mm, flexural strength is at least50 kg/mm² or above. In the case of machining the material to have a wallthickness of 0.1 mm or under, the flexural strength is 75 kg/mm² orgreater. Deterioration due to chips can be minimized by selecting theceramic materials which meet such requirements.

A member formed of an Si₃ N₅ group material or a ZrO₂ group material orformed of a composite obtained by adding other oxide, carbide, nitrideand boride among the foregoing materials thereto is capable of providinga well-conditioned finish and decreasing the thickness of each blade ofthe stabilizer. Hence, it is possible to reduce resistance duringstraightening of the water jets, ameliorate hyperfine machinability ofthe needle tip and enhance the function of the nozzle itself.

Characteristics of the present invention will be described hereinafterin detail with reference to the accompanying drawings showing anembodiment thereof.

FIG. 1 is a view sectionally showing in perspective an outer shape of anozzle member 1 according to the present invention. The nozzle member 1is constructed such that, as illustrated in FIG. 1, a stabilizer 5 isintegrally formed through an annular groove 4 for adjusting the waterflow at the rear of an orifice 3 formed in an interior of a body 2 atits rear end.

The stabilizer 5 is, as shown in section in FIG. 2, formed with morethan 10 streaks of slits 6 each having the same width at equal spacings.

Equalization of the spacings between the slits is of great importance interms of high-speed straightening of water flow. The best condition hasbeen confirmed from experiments, wherein the number of slits each havinga width of 0.5 mm is 16 to 18 when the number of revolutions of a loomis 900 rpm and the pump water pressure is 35 kg/cm².

To express this optimal configuration in terms of dimensions, the numberof slits 6 should be adjusted depending on the size of the insidediameter of the stabilizer. In this case, the thickness of the top endof a blade 7 formed between slits 6, shown in FIG. 2, is 0.1 mm orunder, preferably smaller than 0.05 mm. It is feasible to obtain a jetwater flow having a higher convergence as it approaches a knife edge.

If a ceramic material such as zirconia is employed, it is possible toeasily adjust the accuracy of the width to within ±0.01 mm, andaccordingly the water jet flow generated in the orifice can be speededup and controlled.

Turning to FIG. 3, illustrating a sectional configuration of the nozzlemember 1 including an integrally formed orifice and stabilizer, athickness of an outside diameter of each of the blades 7 for shaping theslits 6 of the stabilizer 5 is set preferably to 0.5 mm through 1.2 mm.A top end 8 of the blade 7 may be formed at a right angle or anotherangle or be rounded with a radius. However, a preferable formationthereof eliminates the possibility of producing chips. A corner of anorifice inlet 11 facing an annular groove 4 formed to reduce theresistance of a rectified water pressure is formed in a round shapehaving a radius of at least 0.5 mm. An angle θ of a tapered portion 12is, as illustrated in FIG. 4, set at 6° through 11°, and it follows thatsubsequent water jet flows are effectively generated. Referring to FIG.3, the numeral 9 represents a needle for feeding out the weft yarn setin a central opening of the orifice 3 of the nozzle member 1 as well asin a central part of the stabilizer 5 shown in FIG. 1.

Injected water W completely rectified by the stabilizer 5 in cooperationwith the annular groove 4 is jetted between the needle 9 and the orifice3. When jetting the water W, an edge angle of a top end 10 of theorifice 3 is preferably larger than 90° under such a condition that therectified water W runs at a high flow rate of 30-40 m/sec. Morepreferably, the edge angle is set at 95° to 115°, with the result that awater jet flow having a good convergence can be attained withoutsplitting the flow. An additional condition for obtaining a highlyconvergent water jet flow is that the edge portion having an angle of95° through 115° is shaped to provide a smooth surface without producingchips to the greatest possible degree.

The water jet nozzle assuming configurations shown in the foregoingfigures is composed of partially-stabilized zirconia and many othermaterials in the manner discussed above and is applied to a loom inwhich synthetic long fibers are arranged with a taffeta width of1200-1800 mm. In this case, weaving can be effected at a higher velocityof 200-400 times/min (approximately 1.5-fold velocity) than in theconventional nozzle.

In the prior art, a sizing process of the warp is needed because ofhair-rising thereof. As a result of effecting the operation by use ofthe nozzle of this invention, well-conditioned fabrics can be obtainedwith no hair-rising. A probability of non-sizing can be realizeddepending on types of textiles employed.

The present invention yields the following advantages:

(1) The nozzle member constructed of the stabilizer and the orificewhich are formed integrally and the needle are made of the materials ofhigh hardness and corrosion resistance, thereby exhibiting a longstretch of durability against hyperfast water jets generated therein;

(2) Since the stabilizer is shaped integrally with the orifice, thenozzle can simply be assembled and adjusted;

(3) A functional correlation between the nozzle member comprising thestabilizer and the orifice integral therewith and the needle can beestablished, and a more accurate nozzle function can thereby beexpected;

(4) A higher speed water flow than in the prior art can be obtained witha lesser amount of water;

(5) The insertion of weft yarn can be performed stably at a highvelocity, which markedly reduces lack of uniformity of weaving; and

(6) Labor for maintenance is considerably reduced, and the availabilityfactor of the loom is outstandingly improved.

The water jet nozzle of the present invention can be applied to ahigh-speed loom by which fabrics that are required to have a highquality are manufactured.

high quality are manufactured.

We claim:
 1. A water jet nozzle for a loom comprising a nozzle memberhaving a rear end portion; orifice means defining an interior orifice insaid rear end portion; stabilizer means integrally connected to saidorifice means for adjusting water flow in said rear end portion of saidnozzle member, said orifice means and said stabilizer means defining anannular groove therebetween and being made of a material having a highhardness and high corrosion resistance; and a needle arranged centrallyof said orifice means for feeding out a weft yarn.
 2. A water jet nozzleas in claim 1, wherein said material of said orifice means and saidstabilizer means is selected from the group consisting of cementedcarbides, cermets and ceramics having a modulus of elasticity greaterthan 1.5×10⁴ kg/mm, an H_(R) A hardness of at least 85, and a flexuralstrength of at least 50 kgmm².
 3. A water jet nozzle as in claim 2,wherein said material has a flexural strength of at least 75 kg/mm². 4.A water jet nozzle as in claim 1, wherein said material of said orificemeans and said stabilizer means comprises partially-stabilized zirconia.5. A water jet nozzle as in claim 1, wherein said stabilizer meanscomprises a plurality of elongated blades of equal width arranged inconcentric parallel spaced relation, said blades defining therebetween aplurality of elongated slits of equal width arranged in concentricparallel spaced relation.
 6. A water jet nozzle as in claim 5, whereineach of said plurality of blades tapers radially inwardly from arelatively wider outer end to a relatively narrower inner end.
 7. Awater jet nozzle as in claim 6, wherein the outer end of each of saidplurality of blades has a width ranging from 0.5 mm to 1.2 mm, and theinner end of each of said plurality of blades has a width of no greaterthan 0.1 mm.
 8. A water jet nozzle as in claim 1, wherein said orificemeans tapers inwardly from said rear end portion of said nozzle member.9. A water jet nozzle as in claim 8, wherein said orifice means tapersinwardly at an angle ranging from 6° to 11°.
 10. A water jet nozzle asin claim 1, wherein said orifice means further comprises a front edgehaving an angle of at least 90° and a rear edge facing said angulargroove and having a round shape with a radius of at least 0.5 mm.
 11. Awater jet nozzle as in claim 10, wherein said front edge has an angle of95° to 115°.